The printing of images on curved surfaces, such as those of preformed plastic containers, has generally involved the use of offset printing where multiple color printings are required. These are formed by a plurality of printing stations arranged around the printing blanket to print separate one color images of ink thereon for transfer to the container. In my prior U.S. Pat. No. 4,774,885, there is described the provision of a reproduction of a photograph on a preformed container using such offset printing.
Such offset printing involves the use of very thin metal lithographic printing plates which possess very little or no relief which leads to very little or no distortion of the image when printed on a curved surface.
Flexographic printing has become a popular printing procedure in recent years, in which a flexible printing plate, for example, CYREL.RTM. photopolymer plates, having a relief image formed thereon, is used to print a recipient surface.